Analysis of Fusarium graminearum Species Complex from Freshly Harvested Rice in Jiangsu Province (China)

Members of Fusarium graminearum species complex (FGSC) are the major pathogens that cause Fusarium head blight (FHB) in cereals worldwide. Symptoms of FHB on rice, including dark staining or browning of rice glumes, were recently observed in Jiangsu Province, China. To improve our understanding of the pathogens involved, 201 FGSC isolates were obtained from freshly harvested rice samples and identified by phylogenetic analyses. Among the 201 FGSC isolates, 196 were F. asiaticum and the remaining 5 were F. graminearum. Trichothecene chemotype and chemical analyses showed that 68.4% of the F. asiaticum isolates were the 3-acetyldeoxynivalenol (3ADON) chemotype and the remainder were the nivalenol (NIV) chemotype. All of the F. graminearum isolates were the 15-acetyldeoxynivalenol chemotype. Pathogenicity assays showed that both the 3ADON and NIV chemotypes of F. asiaticum could infect wheat and rice spikes. FHB severity and trichothecene toxin analysis revealed that F. asiaticum with the NIV chemotype was less aggressive than that with the 3ADON chemotype in wheat, while the NIV-producing strains were more virulent than the 3ADON-producing strains in rice. F. asiaticum isolates with different chemotypes did not show significant differences in mycelial growth, sporulation, conidial dimensions, or perithecial production. These findings would provide useful information for developing management strategies for the control of FHB in China.

Potassium Iodide Reversal of Silver Diamine Fluoride Staining: A Case Report

SUMMARYThis article describes the clinical protocol of using potassium iodide (KI) to reverse staining caused by silver diamine fluoride (SDF). SDF contains silver, fluoride, and ammonia. It has been used to arrest dental caries mainly in pediatric applications. The major drawback of SDF application is the dark staining of both teeth and restorative materials. Hence, its use on adult dentition is limited. Improving the esthetic outcome by stain reduction would greatly enhance the opportunity for SDF's universal use. This case demonstrates how KI can effectively reverse the staining.

Role of chromohysteroscopy in detection of endometrial pathology in abnormal uterine bleeding

Background: Abnormal uterine bleeding is one of the most common clinical problems encountered in gynaecological practice. Chromohysteroscopy is thought to improve the diagnostic accuracy of hysteroscopy and reach the final diagnosis in AUB and is the subject matter of this study.Methods: A prospective cross-sectional study was performed on 35 women with AUB, who presented to the Dept. of Obstetrics and Gynecology, JNMCH, Aligarh, over a period of 2 years (2014-2016). After transvaginal sonography, all cases underwent hysteroscopy followed by chromohysteroscopy using 5% methylene blue dye. Differentially stained pattern of the uterine cavity was observed and hysteroscopic guided biopsy was taken from stained and unstained areas, followed by endometrial aspiration biopsy. All three samples were sent for histopathological examination. Results were analyzed and compared.Results: Out of 35 cases studied, 13 cases showed diffuse light staining, while 22 cases had focal dark staining. Histopathology results from diffuse light stained group showed 9 (69.2%) had normal endometrium. Out of 22 cases with focal dark staining, 20 (90.0%) cases had abnormal histopathology. It was found that focal dark staining to detect endometrial pathology had a sensitivity of 83.3%, specificity of 81.8%, positive predictive value of 90.9 %, negative predictive value of 69.2% and accuracy 82.8%. The difference in the diagnostic ability of stained tissue biopsy was highly significant (p< 0.001) when compared to blind endometrial aspiration biopsy.Conclusions: Chromohysteroscopy is an efficacious simple tool for detecting endometrial pathology in cases of AUB.

The Moyjil site, south-west Victoria, Australia: fire and environment in a 120,000-year coastal midden — nature or people?

At Moyjil (Point Ritchie), a cliffed site at the mouth of the Hopkins River at Warrnambool, south-eastern Australia, an erosional disconformity of Last Interglacial age on both a rock stack and the adjacent headland represents a surface of possible human occupation. Shells of edible marine molluscs occur on the disconformity, together with a distinctive population of transported stones derived from a calcrete of MIS 7 age and bearing variable dark grey to near-black colouration suggestive of fire. Experimental fire produced similar thermal alteration of calcrete. A strong correlation exists between intensity and depth of dark staining on one hand and increased magnetic susceptibility on the other. Thermal luminescence analyses of blackened stones provide ages in the MIS 5e range, 100–130 ka, consistent with independent stratigraphic evidence and contemporaneous with the age of the surface on which they lie. The distribution of fire-darkened stones is inconsistent with wildfire effects. Two hearth-like features closely associated with the disconformity provide further indications of potential human agency. The data are consistent with the suggestion of human presence at Warrnambool during the Last Interglacial.

Characterization of a Major Bacillus anthracis Spore Coat Protein and Its Role in Spore Inactivation

ABSTRACT A major Bacillus anthracis spore coat protein of 13.4 kDa, designated Cotα, was found only in the Bacillus cereus group. A stable ca. 30-kDa dimer of this protein was also present in spore coat extracts. Cotα, which is encoded by a monocistronic gene, was first detected late in sporulation, consistent with a σK-regulated gene. On the basis of immunogold labeling, the protein is in the outer spore coat and absent from the exosporium. In addition, disruption of the gene encoding Cotα resulted in spores lacking a dark-staining outer spore coat in thin-section electron micrographs. The mutant spores were stable upon heating or storage, germinated at the same rate as the wild type, and were resistant to lysozyme. They were, however, more sensitive than the wild type to phenol, chloroform, and hypochlorite but more resistant to diethylpyrocarbonate. In all cases, resistance or sensitivity to these reagents was restored by introducing a clone of the cotα gene into the mutant. Since Cotα is an abundant outer spore coat protein of the B. cereus group with a prominent role in spore resistance and sensitivity, it is a promising target for the inactivation of B. anthracis spores.

Wood-Destroying Soft Rot Fungi in the Historic Expedition Huts of Antarctica

ABSTRACT Three expedition huts in the Ross Sea region of Antarctica, built between 1901 and 1911 by Robert F. Scott and Ernest Shackleton, sheltered and stored the supplies for up to 48 men for 3 years during their explorations and scientific investigation in the South Pole region. The huts, built with wood taken to Antarctica by the early explorers, have deteriorated over the past decades. Although Antarctica has one of the coldest and driest environments on earth, microbes have colonized the wood and limited decay has occurred. Some wood in contact with the ground contained distinct microscopic cavities within secondary cell walls caused by soft rot fungi. Cadophora spp. could be cultured from decayed wood and other woods sampled from the huts and artifacts and were commonly associated with the soft rot attack. By using internal transcribed spacer sequences of ribosomal DNA and morphological characteristics, several species of Cadophora were identified, including C. malorum, C. luteo-olivacea, and C. fastigiata. Several previously undescribed Cadophora spp. also were found. At the Cape Evans and Cape Royds huts, Cadophora spp. commonly were isolated from wood in contact with the ground but were not always associated with soft rot decay. Pure cultures of Cadophora used in laboratory decay studies caused dark staining of all woods tested and extensive soft rot in Betula and Populus wood. The presence of Cadophora species, but only limited decay, suggests there is no immediate threat to the structural integrity of the huts. These fungi, however, are widely found in wood from the historic huts and have the capacity to cause extensive soft rot if conditions that are more conducive to decay become common.

Pollen viability of ‘Besztercei plum' clones depending on the effect of the year

The percentage of dark staining pollen grains was higher in spring of 1996 than in the previous year. Data in 1998 resemble those of 1995, concerning the large amount of medium staining pollen grains in the majority of clones. Some clones produced excellent quality pollen also in the third year. whereas there were significant differences in other clones in various years. The warmer February-March period in 1995 induced an early blooming, and frost affected the orchard not only in winter months, but also immediately before and during blooming. Thus, frost was the possible cause of weaker quality pollen this year. In 1996 warming began a bit late, but it was not broken by drastic falls in temperature, except for the middle of April, when a smaller frost affected the orchard. It is likely that this frost did not influence pollen quality of `Besztercei' and 'Early Besztercei' plum clones significantly. In 1998 warming was continuous and steady, the orchard was not affected by frost immediately before blooming. In March, however, there was frost almost every day, according to daily minimum temperatures.

Metamorphosis in the summer flounder Paralichthys dentatus: changes in gill mitochondria-rich cells

Salinity tolerance changes during larval development and metamorphosis in the summer flounder (Paralichthys dentatus) and other teleosts. The physiological mechanisms responsible for osmoregulation during these early stages of development are not well understood. This study characterized changes in ultrastructure, intracellular membranes and immunoreactive Na(+)/K(+)-ATPase of mitochondria-rich cells (MRCs) in the gills of summer flounder during metamorphosis. Gill ultrastructure at the start of metamorphosis revealed only one type of MRC, which had weak reactivity to osmium and lacked a well-defined apical pit. In juveniles, two types of MRCs were observed: light-staining MRCs (LMRCs) with weak reactivity to osmium, and dark-staining MRCs (DMRCs) with strong reactivity to osmium and positioned adjacent to LMRCs. Compared with MRCs at the start of metamorphosis, the mitochondria of juvenile MRCs appeared smaller, with more transverse cristae and electron-dense matrices. Changes in MRCs during metamorphosis were also accompanied by increased immunoreactive Na(+)/K(+)-ATPase. These findings suggest that gill MRCs develop during the metamorphosis of summer flounder as the gill takes on an increasingly important osmoregulatory role.

Metanephric Adenoma–like Tumors of the Kidney: Report of 3 Malignancies With Emphasis on Discriminating Features

Background.—Metanephric adenoma is a very rare benign renal tumor; only 80 well-documented cases have been reported to date. We have seen several renal tumors that were originally incorrectly diagnosed as metanephric adenoma. Design.—We present 3 unusual renal tumors (2 primary and 1 metastatic), each of which illustrates important pathologic features useful in discriminating metanephric adenoma from malignant mimics. Results.—Case 1 involved a 46-year-old man with multiple small, cortical, solid, papillary (chromophil) renal cell carcinomas in his right kidney; the patient developed multiple, histologically identical, solid, papillary (chromophil) carcinomas in the opposite kidney 17 months later. Case 2 involved a 32-year-old woman with a 14-cm right renal tumor who developed soft tissue and bone metastases over a 17-year period. Case 3 involved a 52-year-old woman who presented with a 1.8-cm corticomedullary renal nodule, which eventually proved to represent a metastasis from a poorly differentiated (insular) carcinoma of the thyroid. All 3 tumors superficially resembled metanephric adenoma and consisted of primitive, dark-staining cells arranged in tubules or sheets. Each tumor, however, also had features inconsistent with the diagnosis of metanephric adenoma, including multifocal lesions with a variable nuclear-cytoplasmic ratio and diffuse cytokeratin 7 and epithelial membrane antigen immunopositivity in case 1, a 14-cm-diameter tumor with occasional mitoses in case 2, and a distinct fibrous capsule with capsular and vascular invasion in case 3. In addition, all 3 tumors lacked the cytologic features of bland overlapping nuclei with imperceptible cytoplasm consistently seen in metanephric adenoma. Conclusion.—Adherence to strict histopathologic criteria will discourage misdiagnosis of a malignant or potentially malignant renal neoplasm as the rare and always benign metanephric adenoma.

Reconstructing reproductive histories of black bears from the incremental layering in dental cementum

Known reproductive histories of female radio-collared black bears (Ursus americanus) in Minnesota were matched against the spacing of growth layers in stained thin sections of their teeth. Light-staining bands of cementum, deposited during the summer months, were relatively narrow during years when females were raising cubs. Because females in this study never successfully reared cubs in 2 consecutive years, narrow light bands were bordered by wider bands, causing the intervening dark-staining fall–winter annuli to appear paired. Adult males exhibited similar pairing of dark annuli, caused not by altered annular spacing but by deposition of distinct summer accessory lines. Paired dark annuli in females accurately reflected known cub-rearing records, although it was more difficult to determine the years of cub production (reading teeth from the outer annulus inward) than the ages of females when they produced cubs (counting annuli outward from the dentin–cementum interface). The distribution of ages of first reproduction gleaned from teeth of harvested females coincided with that of females with known reproductive histories, indicating that teeth currently collected from harvested black bears by management agencies across North America could provide reasonably good accounts of both present and past reproductive rates.